Embodiments of the present disclosure relate to protection of electrical circuits, and more particularly to a system and method for quenching of an arc in the electrical circuits.
Protecting electrical devices from fault conditions such as an over-current condition or an over-temperature condition is of utmost importance while configuring home and industrial electrical setups. Faults in a main power supply or faults resulting from short circuit conditions may result in the malfunctioning of the electrical devices and/or damage the electrical devices. Therefore, it is desirable to interrupt the current flowing through the electrical devices on occurrence of such faults in order to protect the electrical devices.
Currently, during the fault condition a device such as a circuit breaker is employed to interrupt the current flowing through the electrical devices connected to the circuit breaker. Use of the circuit breaker is more prevalent than use of a fuse due to reusability of the circuit breaker. The fuse once burnt needs to be replaced in order to resume supply of the current. The circuit breaker may be used to sense the over-current condition, the over-temperature condition, and a manual interruption of the current. Once the fault condition is detected, the circuit breaker is used to interrupt the current flowing through the electrical devices that are connected to the circuit breaker.
In general, the circuit breaker typically includes a fixed contact and a moving contact detachably coupled to the fixed contact. Under normal operating conditions, such coupling of the fixed contact and the moving contact allows the current to flow through the circuit breaker. On occurrence of a fault such as the over-current condition and/or the over-temperature condition, the moving contact separates from the fixed contact to interrupt the flow of the current. Additionally, manual interruption of the current flowing through the circuit breaker may also result in separation of the moving contact from the fixed contact. However, the separation of the moving contact from the fixed contact may generate an arc between the moving contact and the fixed contact as the current still continues to flow.
The presence of this arc between the moving contact and the fixed contact leads to undesirable results. For example, the presence of the arc allows the current to flow for a certain period of time even after the separation of the fixed contact and the moving contact. Also, the arc may re-strike due to increased temperature and presence of highly ionized air between the fixed contact and the moving contact. This re-striking of the arc also allows the current to flow through the electrical devices. Therefore, it is desirable to mitigate the arc expeditiously.
One such solution to mitigate the arc is to use an arc quenching system such as an arc chute. Currently available arc chutes include multiple stationary arc chute plates made of conductive materials such as metals. These arc chute plates are held together proximate to the fixed contact and the moving contact. Magnetic and/or gaseous forces produced due to the arc and the presence of the arc chute plates force the arc to move into the arc chute. Consequently, the arc is divided between the arc chute plates. This division of the arc allows the arc to be broken and diminished.
In the process of dividing the arc, the arc chute plates may get damaged due to erosion of the arc chute plates caused by hot spots where the arc strikes the arc chute plates. Therefore, the lifetime of the arc chute and hence the lifetime of the circuit breaker is reduced. Moreover, the erosion of the arc chute plates results in a formation of metal vapor near the fixed contact and the moving contact. The metal vapor may increase the conductivity of plasma between the fixed contact and the moving contact. Therefore, in the conventional arc quenching systems where the arc chute plates are stationary, the possibility of arc re-striking severely diminishes the performance of the circuit breaker.